Alloy



Patented Dec. 23, 1941 UNITED STATES PATENT, OFFICE ALLOY Reginald s. Dean, Salt Lake City, Utah, assignor to Chicago Development Company, Chicago, 111., a corporation of Illinois No Drawing. Application March 24, 1941,

Serial No. 384,957 I 4 Claims.

It has heretofore been recognized that high brass containing approximately 64% to 68% copper and balance substantially all zinc can be hot rolled satisfactorily only if the lead content thereof is exceedingly low. For example, if such brass contains 0.02% lead, it may be hot rolled at any temperature between about 1500 degrees F. and about 1650 degrees F. With 0.1% lead, this temperature range of rolling is reduced to 1550 degrees F. to 1625 degrees F. while with 0.18% lead, there is no temperature above room temperature atuwhicli the said brass can be fully successfully r ed.

In accordance with my present invention, I have discovered that the addition of from about 1% to about 3% of manganese -to brass containing approximately 64% to 68% copper and balance substantially all zinc permits a satisfactory is as high as 0.35%. By the use of my invention,

a suitable rolling range is from about 1450 degrees F. to about 1550 degrees F. This increase in hot rollability, by the addition of from 1% t0 3% of manganese. is brought about without ad- :ed y affecting other physical properties of the rass.

In accordance with my invention. the use of 2% of manganese in a brass of the character hereinabove described results in the production of hot rolled sheets wherein the tensile strength is between 45,000pounds and 50,000 pounds per square inch even though the lead content is between 0.15% and 0.35%. In addition, the elon ation of such an alloy, made in accordance with my invention, is 58% in two inches in the hot rolled condition, which is substantially equal to the elongation of an alloy of 64% copper and 36% zinc and which is substantially free from lead or manganese.

The advantages which the practice of my invention brings about are several. In the first place, the hot rolling technique, which is a faster method of producing sheets, may be carried out without the necessity of using the hishest purity o zinc in the manufacture of the alloy. In the second place, the hot rolling technique is not only cheaper than the cold rolling practice but, in addition, it enables economies in operation since 5 it permits the use of ordinary spelter where the manganese is utilized to offset the difficulties brought about by the presence of the lead impurities present in the cheaper ordinaryspelter.

In order to produce the most satisfactory results, I prefer to employ a high purity manganese in the practice of my invention, that is, a manganese having a purity of at least about 99.0%.

I have found that electrolytic manganese having a purity of 99.9% is especially satisfactory and,

therefore, its use represents the particularly preelements in substantially the indicated percentages by weight:

Copper 64 to 68 Lead 0.1 to 0.35

Manganese 1 to 8 Balance 2. A hot rollable brass containing the following ingredients in substantially the following P rcentages by weight:

Copper 64 to 68 Lead 0.1 to0.85

Electrolytic .manganese 2 Zinc Balance 3. A hot rollable brass containing the following elements in substantially the indicated percent- 4. A hot rollable brass containing the following elements in substantially the indicated percen 5 ages by weight:

Copper 64 Lead 0.1to0-35 Electrolytic manganese 2 Zinc Balance REGINAID 8. DEAN. 

